Install metrics often vary significantly across analytics platforms, leading to confusion. This documentation explains the differences in how NotifyVisitors, Firebase, and the Google Play Store track app installs or first opens. It also clarifies why NotifyVisitors’ install count aligns more closely with Firebase's first_open event than with Play Store install numbers.

Platform-specific behavior

Google play store

The Play Store measures installs strictly based on the successful download and installation of the app from the store. It does not count reinstalls or app updates as new installs. If a user installs the app on multiple devices using the same Google account, it still counts as a single install.

Firebase (first_open event)

Firebase uses the first_open event to track when a user first opens the app after installation. This event is triggered:

• When the app is opened for the first time after installation
• When the app is opened for the first time after being reinstalled
• When the app is opened for the first time after clearing app data
• When the app is opened after user updates to a version that includes Firebase for the first time
• When the app is installed and opened for the first time on a second device

In short, Firebase measures user interactions, not just installs.

NotifyVisitors

As NotifyVisitors does not have access to Play store or App store’s installation data directly, it logs an ‘app_install’ event when the user opens the app for the first time with NotifyVisitors SDK present. This behavior means:

• First-time opens after app installation
• First-time opens after reinstall, app data clearance, or installation on a second device
• First-time opens by existing users after updating to the version where NotifyVisitors SDK is integrated for the first time

Due to these similarities NotifyVisitors’ install count closely matches with Firebase’s first_open, compared to play store installs.

Scenario-based comparison table

Conclusion

The key difference across platforms lies in what event is being measured:

• Play Store tracks technical app installs per Google account.
• Firebase counts the user's first app open after install, reinstall, or data clearance.
• NotifyVisitors tracks first opens, same as firebase but our SDK must be integrated.

For meaningful analytics and consistent comparison, always compare NotifyVisitors’ install numbers with Firebase’s first_open count, not Play Store installs. This ensures a realistic view of how many users are actively engaging with your app.